| // Copyright 2012 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef V8_OPTIMIZING_COMPILER_THREAD_H_ |
| #define V8_OPTIMIZING_COMPILER_THREAD_H_ |
| |
| #include "src/base/atomicops.h" |
| #include "src/base/platform/mutex.h" |
| #include "src/base/platform/platform.h" |
| #include "src/base/platform/time.h" |
| #include "src/flags.h" |
| #include "src/list.h" |
| #include "src/unbound-queue-inl.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| class HOptimizedGraphBuilder; |
| class OptimizedCompileJob; |
| class SharedFunctionInfo; |
| |
| class OptimizingCompilerThread : public base::Thread { |
| public: |
| explicit OptimizingCompilerThread(Isolate* isolate) |
| : Thread(Options("OptimizingCompilerThread")), |
| #ifdef DEBUG |
| thread_id_(0), |
| #endif |
| isolate_(isolate), |
| stop_semaphore_(0), |
| input_queue_semaphore_(0), |
| input_queue_capacity_(FLAG_concurrent_recompilation_queue_length), |
| input_queue_length_(0), |
| input_queue_shift_(0), |
| osr_buffer_capacity_(FLAG_concurrent_recompilation_queue_length + 4), |
| osr_buffer_cursor_(0), |
| osr_hits_(0), |
| osr_attempts_(0), |
| blocked_jobs_(0), |
| tracing_enabled_(FLAG_trace_concurrent_recompilation), |
| job_based_recompilation_(FLAG_job_based_recompilation) { |
| base::NoBarrier_Store(&stop_thread_, |
| static_cast<base::AtomicWord>(CONTINUE)); |
| input_queue_ = NewArray<OptimizedCompileJob*>(input_queue_capacity_); |
| if (FLAG_concurrent_osr) { |
| // Allocate and mark OSR buffer slots as empty. |
| osr_buffer_ = NewArray<OptimizedCompileJob*>(osr_buffer_capacity_); |
| for (int i = 0; i < osr_buffer_capacity_; i++) osr_buffer_[i] = NULL; |
| } |
| } |
| |
| ~OptimizingCompilerThread(); |
| |
| void Run(); |
| void Stop(); |
| void Flush(); |
| void QueueForOptimization(OptimizedCompileJob* optimizing_compiler); |
| void Unblock(); |
| void InstallOptimizedFunctions(); |
| OptimizedCompileJob* FindReadyOSRCandidate(Handle<JSFunction> function, |
| BailoutId osr_ast_id); |
| bool IsQueuedForOSR(Handle<JSFunction> function, BailoutId osr_ast_id); |
| |
| bool IsQueuedForOSR(JSFunction* function); |
| |
| inline bool IsQueueAvailable() { |
| base::LockGuard<base::Mutex> access_input_queue(&input_queue_mutex_); |
| return input_queue_length_ < input_queue_capacity_; |
| } |
| |
| inline void AgeBufferedOsrJobs() { |
| // Advance cursor of the cyclic buffer to next empty slot or stale OSR job. |
| // Dispose said OSR job in the latter case. Calling this on every GC |
| // should make sure that we do not hold onto stale jobs indefinitely. |
| AddToOsrBuffer(NULL); |
| } |
| |
| static bool Enabled(int max_available) { |
| return (FLAG_concurrent_recompilation && max_available > 1); |
| } |
| |
| #ifdef DEBUG |
| static bool IsOptimizerThread(Isolate* isolate); |
| bool IsOptimizerThread(); |
| #endif |
| |
| private: |
| class CompileTask; |
| |
| enum StopFlag { CONTINUE, STOP, FLUSH }; |
| |
| void FlushInputQueue(bool restore_function_code); |
| void FlushOutputQueue(bool restore_function_code); |
| void FlushOsrBuffer(bool restore_function_code); |
| void CompileNext(); |
| OptimizedCompileJob* NextInput(); |
| |
| // Add a recompilation task for OSR to the cyclic buffer, awaiting OSR entry. |
| // Tasks evicted from the cyclic buffer are discarded. |
| void AddToOsrBuffer(OptimizedCompileJob* compiler); |
| |
| inline int InputQueueIndex(int i) { |
| int result = (i + input_queue_shift_) % input_queue_capacity_; |
| DCHECK_LE(0, result); |
| DCHECK_LT(result, input_queue_capacity_); |
| return result; |
| } |
| |
| #ifdef DEBUG |
| int thread_id_; |
| base::Mutex thread_id_mutex_; |
| #endif |
| |
| Isolate* isolate_; |
| base::Semaphore stop_semaphore_; |
| base::Semaphore input_queue_semaphore_; |
| |
| // Circular queue of incoming recompilation tasks (including OSR). |
| OptimizedCompileJob** input_queue_; |
| int input_queue_capacity_; |
| int input_queue_length_; |
| int input_queue_shift_; |
| base::Mutex input_queue_mutex_; |
| |
| // Queue of recompilation tasks ready to be installed (excluding OSR). |
| UnboundQueue<OptimizedCompileJob*> output_queue_; |
| // Used for job based recompilation which has multiple producers on |
| // different threads. |
| base::Mutex output_queue_mutex_; |
| |
| // Cyclic buffer of recompilation tasks for OSR. |
| OptimizedCompileJob** osr_buffer_; |
| int osr_buffer_capacity_; |
| int osr_buffer_cursor_; |
| |
| volatile base::AtomicWord stop_thread_; |
| base::TimeDelta time_spent_compiling_; |
| base::TimeDelta time_spent_total_; |
| |
| int osr_hits_; |
| int osr_attempts_; |
| |
| int blocked_jobs_; |
| |
| // Copies of FLAG_trace_concurrent_recompilation and |
| // FLAG_job_based_recompilation that will be used from the background thread. |
| // |
| // Since flags might get modified while the background thread is running, it |
| // is not safe to access them directly. |
| bool tracing_enabled_; |
| bool job_based_recompilation_; |
| }; |
| |
| } } // namespace v8::internal |
| |
| #endif // V8_OPTIMIZING_COMPILER_THREAD_H_ |